Author Topic: rear shock adjustment  (Read 8454 times)

Charlie P

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Re: rear shock adjustment
« Reply #15 on: September 25, 2017, 07:13:46 PM »
Not sure if the Like has  has a both side and a center stand -but  be sure it's on the center stand when adjusting the shocks.  I tried adjusting my Xciting 500 one time while on its side stand and just couldn't figure out why it was so hard to turn - duh :-[- putting it on the center stand lets the wheel assembly hang down and takes weight off the springs.
Charlie P.
2013 Xciting 500Ri ABS
formerly 2010 Yager & 2008 Grand Vista
Near Haslet, TX (NW of Fort Worth)

kymi

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Re: rear shock adjustment
« Reply #16 on: December 16, 2017, 07:51:12 AM »
Sorry to disappoint you but turning that collar will not affect the spring rate, that is fixed by the length of the spring and the diameter of the wire. That collar is just a spring platform and will only change the ride height, and even then only by a few mm, but that's good if you are a bit on the heavy side or wish to carry a pillion passenger best to leave it on the high setting, otherwise it's worth dropping it down a bit to lower the centre of gravity which will aid stability. If you think you can feel a difference it's probably psychological because the change is so small, I dropped mine down and I can't say it feels any different at all but it was worth doing because I am only 70kg and I doubt that I will ever carry a pillion.

I made a c-spanner to do the job:
« Last Edit: December 16, 2017, 09:14:48 PM by kymi »

Stig / Major Tom

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Re: rear shock adjustment
« Reply #17 on: December 16, 2017, 04:09:52 PM »
Sorry to disappoint you but turning that collar will not affect the spring rate, that is fixed by the length of the spring and the diameter of the wire. That collar is just a spring platform and will only change the ride height, and even then only by a few mm, but that's good if you are a bit on the heavy side or wish to carry a pillion passenger best to leave it on the high setting, otherwise it's worth dropping it down a bit to lower the centre of gravity which will aid stability. If you think you can feel a difference it's probably psychological because the change is so small, I dropped mine down and I can't say it feels any different at all but it was worth doing because I am only 70kg and I doubt that I will ever carry a pillion.

I made a c-spanner to do the job:


No, sorry kymi, can't go along with you on this.
Turning the collar to adjust the preload on the rear shocks is directly related to the load on the scooter. Kymco and Piaggio owner's manuals advise you to set the preload position of the collar to match the load you will be riding with.
Light rider typically = lowest setting.
Rider + passenger + cargo = highest, stiffest setting - spring is more compressed.
Light rider riding on this stiffest, highest, setting will expsrience a rougher ride. It is not one's imagination. Stiffer shock setting equals rougher ride for a lone rider. Some manuals caution that you can lessen control and increase likelihood of damage to the scooter if preload setting is grossly incorrect for the load weight and /or road conditions.
I have never heard of "changed center of gravity" discussed in connection with shock preload settings....but I reckon it is occurring.
Ride comfort and rider control are the reasons for adjustable shock preloads. I recall that PCX does not offer adjustable shocks, while the Forza and Silver Wing do.

Stig
« Last Edit: December 16, 2017, 04:33:13 PM by Stig »
Boston Strong
Rural Ohio

And, I'm feeling a little peculiar.

kymi

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Re: rear shock adjustment
« Reply #18 on: December 16, 2017, 06:53:40 PM »
Sorry again, and I'm apologizing because I've only just joined this forum and don't want to be seen as a stirrer but I come from an engineering background and learnt a lot about suspension from my time building and racing Westfield Sports Cars.

The information in the owner's manual is correct and good advice, a higher load should be compensated for by increasing the ride height and that's exactly what the adjustable spring platform does, it's a great feature because a scooter may have to deal with a huge variation in load especially if carrying a passenger, however the spring is not 'more compressed' at the higher setting, that would only happen if the spring is topping out the damper unit and that's a bad thing, or to put it another way when you raise the collar you are lifting the whole spring, the top of the spring raises by the same amount as the base so all that changes is the ride height and consequently the centre of gravity.

As I said previously the spring rate is set by the wire size and length of the spring, you can't change that. Racing suspension usually has adjustable damping, that is what controls the stiffness of the suspension and is usually set with a screw or knob on the body of the damper (shock absorber) or sometimes 2 screws for separate bump and rebound adjustment, some high end motorcycles feature this type of suspension.

I find suspension a fascinating subject and nowadays there is a lot of good information available at the click of a mouse, sorry again if I'm coming across as a bit of a smarty pants, that's not my intention, just trying to help.
« Last Edit: December 16, 2017, 09:16:34 PM by kymi »

Stig / Major Tom

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Re: rear shock adjustment
« Reply #19 on: December 17, 2017, 02:20:29 AM »
OK, in spite of what my teenager thinks - I feel that I am still trainable.
So, using the new set of shocks which I have  - I measure the distance between the upper and lower mounting holes and get 13".
This distance cannot change on an unmounted shock - because the spring is under tension and has pushed the shock to its full length.
I can change the pre-set on the spring to 5 different notches - but the unmounted shock will always remain at 13"....Correct?

But if I mount the shock and put the scooter's weight on it - the measured distance between the upper & lower mount points will lengthen if pre-loaded to collar notch (#5)....and shorten if set to pre-load notch #1. But the distance between the mount points will never be greater than the orig. 13".
Correct?

The shock hasn't lengthened, right?, it can't - so what is allowing the scooter to raise or lower as it sits there - if we haven't effectively changed the stiffness of the spring?

Does not the spring 'feel' stiffer as it is compressed from its unloaded 5" (of course it is not truly 'unloaded' in the shock until disassembled) > to a pre-load of 4" ? I thought these shock springs increased their resistance to weight the more they were forced to shorten by that weight?

I don't know.....I'm gonna make a cup of joe before I get a headache.

Appreicate your input.....
Let's have a scooter picture...

Stig

Boston Strong
Rural Ohio

And, I'm feeling a little peculiar.

kymi

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Re: rear shock adjustment
« Reply #20 on: December 17, 2017, 05:10:13 AM »
You're quite right, a suspension unit is designed to work within a certain range and not top or bottom out. In most vehicles this isn't an issue but adding a passenger to a scooter massively increases the downward force and runs the risk of running out of travel (bottoming out). The spring is just like a battery but for storing energy instead of electricity. The springs on the scooter are constant rate so they will compress the same distance for every kg of force so for example a spring may compress 1cm for every 10kg applied, for every cm thereafter it takes another 10kg of force which is being stored as energy that is pushing back at the same force as that applied, so as that energy increases so does the force and it feels like the spring is getting stiffer. So again, you are correct, the spring does 'feel' stiffer because it contains more energy, and it is this energy that pushes the tyre back down on the ground after hitting a bump, it can't do this if the damper is bottoming out, hence the need to adjust the ride height.

Now that we have a load applied to the spring (the weight of the scooter), and we apply an additional force (the weight of a passenger) the spring is forced to compress because it is pushing against the ground, basically. When you raise the spring platform, however, the weight loading on it is constant so there is no additional force over the length of the spring and it just moves upwards. Once again you are correct, it can only do so until the damper runs out of travel.

Just to confuse the issue there are also variable rate springs which are made from tapered wire, kind of like a fishing rod that's been coiled up. These are typically fitted to high performance road cars which still require a soft ride over rough roads but as the coils close up the spring actually does become stiffer and stop the car leaning over too much in corners. Clever stuff.
« Last Edit: December 17, 2017, 05:32:04 AM by kymi »

LidoCA

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Re: rear shock adjustment
« Reply #21 on: December 18, 2017, 09:34:33 PM »
 I just set my shocks to the middle setting. I couldnt figure out which way was best, so I compromised.
Steve
I have ridden well over 17 miles on my scooters.

2013 LIKE 200i LX.
2016 Yamaha SMax
2014 Yamaha Majesty
La Mirada, Ca.

air23jordan99

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Re: recalls for 200i
« Reply #22 on: December 20, 2017, 07:47:48 PM »
Does anyone know of any recalls on the 2015-2017 likes?

Stig / Major Tom

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Re: rear shock adjustment
« Reply #23 on: December 21, 2017, 02:09:49 AM »
Does anyone know of any recalls on the 2015-2017 likes?


There have been NO recalls of any LIKE model to date.
(source the info from the KYMCO USA home page, "RECALLS")

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Stig
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